Many laboratory processes require the shaking of aqueous solution and/or an aqueous solution combined with an immiscible organic solvent. The shaking generally must be controlled with respect to both intensity of agitation and duration to ensure meaningful comparisons of test results. Shaking often generates gases which must be vented from the container in which the solution is disposed. However, neither the shaking equipment nor the venting means should cause the controlled amount of aqueous solution and/or solvent to be splashed from the container.
Many laboratory testing procedures require an aqueous solution to be separated from an organic solvent after a predetermined duration of shaking. Additional organic solvent may then be added to the container having the residual aqueous solution therein. The controlled shaking may then be repeated. The end result of this testing procedure is the extraction of the solvent soluble organic compounds in the aqueous solution without creating an emulsion with the hydrophobic materials in the aqueous phase.
Efficient operation virtually requires the use of fairly large containers for these testing procedures. For example, one liter containers have been found to be desirable for many such testing procedures. Large containers are frequently required because the analytical measurement device, a GC/MS for example, requires high concentrations to ensure accurate detection. Similarly, reliability and reproducibility of test results make it desirable for several tests to be carried out, with the results of the tests being compared, averaged, or the like.
The prior art includes shakers intended for laboratory tests. The most practical prior art shakers for the above described testing procedures are floor-mounted shakers capable of holding and shaking up to four one liter laboratory vessels. This prior art shaker requires the vessels to be sequentially removed from the shaker to permit draining of the solvent and the addition of fresh solvent. The vessels must then be returned to the prior art shaker to repeat the shaking and subsequent draining process. This prior art shaker inherently requires very substantial times for the completion of such tests. Furthermore, the time consuming need to sequentially remove vessels from the prior art shaker yields very significant differences in time between the termination of the shaking and the drainage of solvent from one sample to the next. This results in different experimental findings for each sample.
In view of the above, it is an object of the subject invention to provide an improved laboratory shaker.
It is another object of the subject invention to provide a laboratory shaker that enables a plurality of samples to be shaken, vented and drained under nearly identical laboratory conditions.
An additional object of the subject invention is to provide a laboratory shaker that enables simultaneous shaking of a plurality of samples, and simultaneous inverting of the samples to permit drainage of solvent therefrom.
It is still another object of the invention to provide a laboratory shaker which can be installed in a conventional laboratory hood so that any possibly hazardous solvent vapors can be safely vented.
It is a further object of the subject invention to provide a shaker apparatus that permits secure retention and shaking of vessels in either an upright or inverted condition.